J. W. Spencer— Tor ,'<„;<* about Lab- <h>t<n-h,. 415 



slabs, which are observed in the old beaches, higher than these 

 original sources, can be best accounted for by the theory that 

 they were carried upward by the coast-ice during the time 

 when the continent was undergoing subsidence, and were re- 

 arranged by the waves and shore ice of a later period. 



Let us now return to the lower water margins of Lake On- 

 tario, represented by "Burlington Heights " and "Burlington 

 Beach," which are almost wholly composed of Hudson Eiver 

 pebbles. The former of these ridges is 116 feet and the latter 

 eight feet above the lake. Both of these beaches, of the same 

 materials, skirt much of the western shores of Lake Ontario. 



Their component pebbles and sand appear to have been en- 

 tiseJj transported by the action of shore-ice and waves. At 

 the commencement of the deposit of the beach at 116 feet 

 above the present water, the Dundas valley formed one contin- 

 uous basin with the lake bed. But at that time, as now, only 

 iona of Lake Ontario forming bays were frozen over 

 in winter. The Dundas valley, being a confined arm, was 

 frozen over, and the pebble-laden ice, from the more exposed 

 coast, was drifted by the winds and currents, and packed across 

 tli'' front of the ice-sheet, covering the waters in this arm of the 

 lake, at 111! feet above their present level ; and with annual 

 dissolution of the ice, the small amounts of material transported 

 during the winters began to deposit the barrier, which was in 

 course of time destined to produce "Burlington Heights"— 

 the beach of that day. The location of the " Heights " was in 

 no way produced by the unimportant streams flowing down the 

 Dundas valley, as is apparent, for the Pre-glacial and Liter-gla- 

 cial drainage of the western peninsula of Ontario was turned 

 into Lake Erie before the Terrace Epoch. The false and in- 

 clined bedding of the "Heights" is always toward the lake 

 (the material sometimes consisting of fine beds of sand, and 

 sometimes of clean large gravel) showing that the sti 

 forces proceeded from the side of the lake. In addition to the 

 *ion of the material by ice, the action of the waves in 

 no small degree assisted in the production of this old beach. 



The present "Burlington Beach" is simply a reproduction 

 of the "Heights" since the time when the lake receded to its 

 present level. Burlington Bay is frozen over every winter, but 

 the lake is seldom frozen to a greater extent than enough to 

 Rringea. Yearly much ice shod with pebbles is drifted 

 againsl the western shores of the lake by the action of storms 

 ■'■'"I waves. In this way much of the western end of the lake, 

 although almost against the foot of the Niagara escarpment, has 

 had its shores made up of pebbles and sands of Hudson Eiver 

 formation. A small portion of the shore material may have 

 been derived from the ruin of former beaches at higher "levels. 



